a-a aaa aar aas aau aax ar- ara arr ars aru arx as- asa asr ass asu asx au- aua aur aus aux ax- axa axr axs axx ra- raa rar ras rau rax rra rrr rrs rru rsa rsr rss rsu rsx rua rur rus ruu rux rxr rxs saa sar sas sau sax sr- sra srr srs srx ss- ssa ssr sss ssu ssx sua sur sus suu sux sxs sxu ua- uaa uar uas uau ur- ura urr urs uru urx usa usr uss usu usx uua uur uus uuu uxr uxu xaa xar xas xau xrx xsa xss xus xxx